Clutch brake elements are used to transmit power in a controlled manner between relatively moving members. In some arrangements a rotating driver member may transmit power to a driven member via a clutch brake element that can operate to engage and disengage the driving and driven members. The driving and driven members may be engaged by moving friction material such as material on a friction lining operatively connected to the driving member, into a position where the driving member and the driven member are engaged via the friction material. Such engagement causes transmission of the rotational motion to the driven member which will begin rotating in coordination with the driving member. Thereafter when the driven member is to no longer be driven by the driving member, the friction material is moved to operatively disengage the members and the driven member is no longer moved in response to the driving member.
Clutch brakes can also be used to stop unwanted rotation of a moving member. In such applications a body of a clutch brake is fixed to a frame or other generally immovable structure. Rotation of a moving member is stopped or slowed by engagement of friction material operatively connected with the body, and the moving member. Because the body which is engaged through the friction material is fixed, the moving member is slowed or stopped as desired. Once the rotating member is stopped, the ability to member rotate again is achieved by disengaging the friction material and the rotating member.
In many applications, clutch brake elements are used both for the function of transmitting movement from a driving to a driven member, as well as to stop or slow the rotation of a driving or driven member when desired. One or more clutch brake elements may be used for each purpose based on their configuration.
Constricting clutch brake elements are a type of clutch brake that can be used in high power, high torque applications. In a constricting clutch brake element, a relatively rotatable member is operatively engaged and disengaged by moving friction linings radially inward relative to a body of the clutch brake element to achieve engagement, and radially outward to achieve disengagement. Airflex® type VC clutch brake elements manufactured by Eaton Corporation are an example of constricting clutch brake elements that are utilized in many types of heavy equipment and high torque applications.
In operation of constricting type clutch brake elements, the power is transmitted through a plurality of friction linings. These friction linings wear over time with repeated engagement and disengagement of the clutch brake element. Eventually the friction linings wear to the extent that they need to be replaced. Replacement of the friction linings requires taking the clutch brake element and its associated equipment out of service. Further, changing the friction linings of the clutch brake element requires at least partial disassembly of the element and considerable downtime for the machinery with which the clutch brake element is used.
Constricting clutch brake elements and associated friction linings may benefit from improvements.